US10224635B2 - Spherical lens array based multi-beam antennae - Google Patents

Abstract

A radio frequency antenna uses an array of spherical lens and mechanically movable radio frequency (RF) elements along the surface of the spherical lens to provide cellular coverage for a narrow geographical area. The antenna includes at least two spherical lenses, where each spherical lens has an associated element assembly. Each element assembly has a track that curves along the contour of the exterior surface of the spherical lens and along which a radio frequency (RF) element can move. The antenna also includes a phase shifter configured to adjust a phase of the signals produced by the RF elements. The antenna includes a control mechanism configured to enable a user to move the RF elements along their respective tracks, and automatically configure the phase shifter to modify a phase of the output signals from the elements based on the relative positions between the RF elements.

Description

This application is a continuation of U.S. application Ser. No. 14/958,607, filed Dec. 3, 2015, which claims the benefit of U.S. provisional application No. 62/201,523 filed Aug. 5, 2015. This and all other referenced extrinsic materials are incorporated herein by reference in their entirety. Where a definition or use of a term in a reference that is incorporated by reference is inconsistent or contrary to the definition of that term provided herein, the definition of that term provided herein is deemed to be controlling.

FIELD OF THE INVENTION

The field of the invention is radio frequency antenna technology.

BACKGROUND

The following description includes information that may be useful in understanding the present invention. It is not an admission that any of the information provided herein is prior art or relevant to the presently claimed invention, or that any publication specifically or implicitly referenced is prior art.

As the demand for transmission of high quality content across the cellular network increases, the need for better large-scale cellular antennae that support higher capacity rises. The commonly used sector antenna designs have several drawbacks. First, there is a limited number of ports allowed per sector. Second, sector antenna has marginal pattern and beam performance (e.g., poor isolation between beams in the case of multi-beam antennas, side lobes, etc.).

It has been proposed that using a spherical lens (e.g., a Luneburg lens, etc.) along with radio frequency transceivers can provide better result than traditional sector antenna. For example, U.S. Pat. No. 5,821,908 titled “Spherical Lens Antenna Having an Electronically Steerable Beam” issued to Sreenivas teaches an antenna system capable of producing independently steerable beams using a phased array antenna and a spherical lens. U.S. Pat. No. 7,605,768 titled “Multi-Beam Antenna” issued to Ebling et al. discloses a multi-beam antenna system using a spherical lens and an array of electromagnetic lens elements disposed around the surface of the lens.

However, these antenna systems are not suitable for base station antennae. Thus, there is still a need for effectively utilizing spherical lens in a base station antenna application.

All publications herein are incorporated by reference to the same extent as if each individual publication or patent application were specifically and individually indicated to be incorporated by reference. Where a definition or use of a term in an incorporated reference is inconsistent or contrary to the definition of that term provided herein, the definition of that term provided herein applies and the definition of that term in the reference does not apply.

SUMMARY OF THE INVENTION

In one aspect of the inventive subject matter, an antenna uses an array of spherical lens and mechanically movable elements along the surface of the spherical lens to provide cellular coverage for a narrow geographical area. In some embodiments, the antenna includes at least two spherical lens aligned along a virtual axis. The antenna also includes an element assembly for each spherical lens. Each element assembly has at least one track that curves along the contour of the exterior surface of the spherical lens and along which a radio frequency (RF) element can move. In some embodiment, the track allows the RF element to move in a direction that is parallel to the virtual axis. The antenna also includes a phase shifter that is configured to adjust a phase of the signals produced by the RF elements. The antenna includes a control mechanism that is connected to the phase shifter and the RF elements. The control mechanism is configured to enable a user to move the RF elements along their respective tracks, and automatically configure the phase shifter to modify a phase of the output signals from the elements based on the relative positions between the RF elements.

In some embodiments, the tracks also enable the RF elements to move in a direction that is perpendicular to the virtual axis.

Multiple RF elements can be placed on a single track. In these embodiments, the multiple RF elements on the same track can be moved independently of each other. In addition, the control mechanism is also programmed to coordinate multiple pairs (or groups) of RF elements and to configure a phase shifter to modify a phase of the output signals transmitted from the same pair (or group) of RF elements, so that the signals would be in-phase.

Various objects, features, aspects and advantages of the inventive subject matter will become more apparent from the following detailed description of preferred embodiments, along with the accompanying drawing figures in which like numerals represent like components.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A illustrates an exemplary antenna system of some embodiments.

FIG. 1B illustrates an exemplary control mechanism.

FIGS. 2A and 2B illustrate the front and back perspectives, respectively, of a spherical lens.

FIG. 3 illustrates an alternative antenna system having two-dimensional tracks.

FIGS. 4A and 4B illustrate the front and back perspectives, respectively, of a spherical lens having a two-dimensional track.

FIG. 5 illustrates an antenna that pairs opposite RF elements in the same group.

FIG. 6 illustrates another antenna that pairs opposite RF elements in the same group.

DETAILED DESCRIPTION

Throughout the following discussion, numerous references will be made regarding servers, services, interfaces, engines, modules, clients, peers, portals, platforms, or other systems formed from computing devices. It should be appreciated that the use of such terms is deemed to represent one or more computing devices having at least one processor (e.g., ASIC, FPGA, DSP, x86, ARM, ColdFire, GPU, multi-core processors, etc.) configured to execute software instructions stored on a computer readable tangible, non-transitory medium (e.g., hard drive, solid state drive, RAM, flash, ROM, etc.). For example, a server can include one or more computers operating as a web server, database server, or other type of computer server in a manner to fulfill described roles, responsibilities, or functions. One should further appreciate the disclosed computer-based algorithms, processes, methods, or other types of instruction sets can be embodied as a computer program product comprising a non-transitory, tangible computer readable media storing the instructions that cause a processor to execute the disclosed steps. The various servers, systems, databases, or interfaces can exchange data using standardized protocols or algorithms, possibly based on HTTP, HTTPS, AES, public-private key exchanges, web service APIs, known financial transaction protocols, or other electronic information exchanging methods. Data exchanges can be conducted over a packet-switched network, a circuit-switched network, the Internet, LAN, WAN, VPN, or other type of network.

As used in the description herein and throughout the claims that follow, when a system, engine, or a module is described as configured to perform a set of functions, the meaning of “configured to” or “programmed to” is defined as one or more processors being programmed by a set of software instructions to perform the set of functions.

The following discussion provides example embodiments of the inventive subject matter. Although each embodiment represents a single combination of inventive elements, the inventive subject matter is considered to include all possible combinations of the disclosed elements. Thus if one embodiment comprises elements A, B, and C, and a second embodiment comprises elements B and D, then the inventive subject matter is also considered to include other remaining combinations of A, B, C, or D, even if not explicitly disclosed.

As used herein, and unless the context dictates otherwise, the term “coupled to” is intended to include both direct coupling (in which two elements that are coupled to each other contact each other) and indirect coupling (in which at least one additional element is located between the two elements). Therefore, the terms “coupled to” and “coupled with” are used synonymously.

In some embodiments, the numbers expressing quantities of ingredients, properties such as concentration, reaction conditions, and so forth, used to describe and claim certain embodiments of the inventive subject matter are to be understood as being modified in some instances by the term “about.” Accordingly, in some embodiments, the numerical parameters set forth in the written description and attached claims are approximations that can vary depending upon the desired properties sought to be obtained by a particular embodiment. In some embodiments, the numerical parameters should be construed in light of the number of reported significant digits and by applying ordinary rounding techniques. Notwithstanding that the numerical ranges and parameters setting forth the broad scope of some embodiments of the inventive subject matter are approximations, the numerical values set forth in the specific examples are reported as precisely as practicable. The numerical values presented in some embodiments of the inventive subject matter may contain certain errors necessarily resulting from the standard deviation found in their respective testing measurements.

As used in the description herein and throughout the claims that follow, the meaning of “a,” “an,” and “the” includes plural reference unless the context clearly dictates otherwise. Also, as used in the description herein, the meaning of “in” includes “in” and “on” unless the context clearly dictates otherwise.

Unless the context dictates the contrary, all ranges set forth herein should be interpreted as being inclusive of their endpoints and open-ended ranges should be interpreted to include only commercially practical values. The recitation of ranges of values herein is merely intended to serve as a shorthand method of referring individually to each separate value falling within the range. Unless otherwise indicated herein, each individual value within a range is incorporated into the specification as if it were individually recited herein. Similarly, all lists of values should be considered as inclusive of intermediate values unless the context indicates the contrary.

All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g. “such as”) provided with respect to certain embodiments herein is intended merely to better illuminate the inventive subject matter and does not pose a limitation on the scope of the inventive subject matter otherwise claimed. No language in the specification should be construed as indicating any non-claimed element essential to the practice of the inventive subject matter.

Groupings of alternative elements or embodiments of the inventive subject matter disclosed herein are not to be construed as limitations. Each group member can be referred to and claimed individually or in any combination with other members of the group or other elements found herein. One or more members of a group can be included in, or deleted from, a group for reasons of convenience and/or patentability. When any such inclusion or deletion occurs, the specification is herein deemed to contain the group as modified thus fulfilling the written description of all Markush groups used in the appended claims.

In one aspect of the inventive subject matter, an antenna uses an array of spherical lens and mechanically movable elements along the surface of the spherical lens to provide cellular coverage for a small, focused geographical area. In some embodiments, the antenna includes at least two spherical lens aligned along a virtual axis. The antenna also includes an element assembly for each spherical lens. Each element assembly has at least one track that curves along the contour of the exterior surface of the spherical lens and along which a radio frequency (RF) element can move. In some embodiment, the track allows the RF element to move in a direction that is parallel to the virtual axis. The antenna also includes a phase shifter that is configured to adjust a phase of the signals produced by the RF elements. The antenna includes a control mechanism that is connected to the phase shifter and the RF elements. The control mechanism is configured to enable a user to move the RF elements along their respective tracks, and automatically configure the phase shifter to modify a phase of the output signals from the elements based on the relative positions between the RF elements.

FIG. 1A illustrates anantenna system100 according to some embodiments of the inventive subject matter. In this example, theantenna system100 includes twospherical lenses105 and110 that are aligned along avirtual axis115 in a three-dimensional space. It is noted that although only two spherical lenses are shown in this example, more spherical lens can be aligned along thevirtual axis115 in theantenna system100. A spherical lens is a lens with a surface having a shape of (or substantially having a shape of) a sphere. As defined herein, a lens with a surface that substantially conform to the shape of a sphere means at least 50% (preferably at least 80%, and even more preferably at least 90%) of the surface area conforms to the shape of a sphere. Examples of spherical lenses include a spherical-shell lens, the Luneburg lens, etc. The spherical lens can include only one layer of dielectric material, or multiple layers of dielectric material. A conventional Luneburg lens is a spherically symmetric lens that has multiple layers inside the sphere with varying indices of refraction.

Theantenna system100 also includes anelement assembly120 associated with thespherical lens105, and anelement assembly125 associated with thespherical lens110. Each element assembly includes at least one track. In this example, theelement assembly120 includes atrack130 while theelement assembly125 includes atrack135. As shown, each of thetracks130 and135 has a shape that substantially conforms to (curves along) the exterior surface of its associated spherical lens. Thetracks130 and135 can vary in length and in dimensions. In this example, thetracks130 and135 are one-dimensional and oriented along thevirtual axis115. In addition, each of thetracks130 and135 covers less than half of a circle created by the respective spherical lens. However, it is contemplated that thetracks130 and135 can have different orientation (e.g., oriented in perpendicular to thevirtual axis115, etc.), can be two-dimensional (or multi-dimensional), and/or can cover smaller or larger portions of the surface areas of thespherical lenses105 and110 (e.g., covering a circumference of a circle created by thespherical lenses105 and110, covering a hemispherical area of thespherical lenses105 and110, etc.).

Each of theelement assemblies120 and125 also houses at least one RF element. An RF element can include an emitter, a receiver, or a transceiver. As shown, theelement assembly120 houses anRF element140 on thetrack130, and theelement assembly125 houses anRF element145 on thetrack135. In this example, each of theelement assemblies120 and125 only includes one RF element, but it has been contemplated that each element assembly can house multiple RF elements on one or more tracks.

In some embodiments, each RF element (fromRF elements140 and145) is configured to transmit an output signal (e.g., a radio frequency signal) in the form of a beam to the atmosphere through its corresponding spherical lens. The spherical lens allows the output RF signal to narrow so that the resultant beam can travel a farther distance. In addition, theRF elements140 and145 are configured to receive/detect incoming signals that have been focused by thespherical spheres105 and110.

Each RF element (of theRF elements140 and145) is physically connected to (or alternatively, communicatively coupled with) a phase shifter for modifying a phase of the output RF signal. In this example, theRF element140 is communicatively coupled to aphase shifter150 and theRF element145 is communicatively coupled to aphase shifter155. Thephase shifters150 and155 are in turn physically connected to (or alternatively, communicatively coupled with) acontrol mechanism160.

In some embodiments, thecontrol mechanism160 includes a mechanical module configured to enable a user to mechanically move theRF elements140 and145 along thetracks130 and135, respectively. The interface that allows the user to move the RF elements can be a mechanical rod or other physical trigger. It is noted that the mechanical rod can have a shape such as a cylinder, a flat piece of dielectric material, or any kind of elongated shapes. In some embodiments, thecontrol mechanism160 also includes an electronic device having at least one processor and memory that stores software instructions, that when executed by the processor, perform the functions and features of thecontrol mechanism160. The electronic device of some embodiments is programmed to control the movement of theRF elements140 and145 along thetracks130 and135, respectively. The electronic device can also provides a user interface (e.g., a graphical user interface displayed on a display device, etc.) that enables the user to control the movement of theRF elements140 and145. The electronic device can in turn be connected to a motor that controls the mechanical module. Thus, the motor triggers the mechanical module upon receiving a signal from the electronic device.

For example, thecontrol mechanism160 can move theRF element140 from position ‘a’ (indicated by dotted-line circle) to position ‘b’ (indicated by solid-line circle) along thetrack130, and move theRF element145 from position ‘c’ (indicated by dotted-line circle) to position ‘d’ (indicated by solid-line circle) along thetrack135. By moving the RF elements to different positions, theantenna system100 can dynamically change the geographical coverage area of theantenna100. It is also contemplated that by moving multiple RF elements and arranging them in different positions, theantenna system100 can also dynamically change the coverage size, and capacity allocated to different geographical areas. As such, theantenna system100, via thecontrol mechanism160, can be programmed to configure the RF elements to provide coverage at different geographical areas and different capacity (by having more or less RF elements covering the same geographical area) depending on demands at the time.

For example, as thecontrol mechanism160 moves theRF elements140 and145 from positions ‘a’ and ‘c’ to positions ‘b’ and ‘d,’ respectively, theantenna system100 can change the geographical coverage area to an area that is closer to theantenna system100. It is also noted that having multiple spherical lenses with associated RF element allow theantenna system100 to (1) provide multiple coverage areas and/or (2) increase the capacity within a coverage area. In this example, since both of theRF elements140 and145 associated with thespherical lenses105 and110 are directing resultant output signal beams at the same direction as indicated byarrows165 and170, theantenna system100 effectively has double the capacity for the coverage area when compared with an antenna system having only one spherical lens with one associated RF element.

However, it is noted that in an antenna system where multiple spherical lenses are aligned with each other along a virtual axis (e.g., the virtual axis115), when multiple RF elements are transmitting output RF signals through the multiple spherical lenses at an angle that is not perpendicular to the virtual axis along which the spherical lenses are aligned, the signals from the different RF elements will be out of phase. In this example, it is shown from the dotted lines175-185 that the output signals transmitted by theRF elements140 and145 at positions ‘b’ and ‘d,’ respectively, are out of phase. Dotted lines175-185 are virtual lines that are perpendicular to the direction of the resultant output signal beams transmitted fromRF elements140 and145 at positions ‘b’ and ‘d,’ respectively. As such, dotted lines175-185 indicate positions of advancement for the resultant output beams. When the output signal beams are in phase, the output signal beams should have the same progression at each of the positions175-185. Assuming bothRF elements140 and145 transmit the same output signal at the same time, without any phase adjustments, the output signal beams165 and170 would have the same phase at the time they leave thespherical lenses105 and110, respectively. As shown, due to the directions the beams are transmitted with respect to how thespherical lenses105 and110 are aligned (i.e., the orientation of the virtual axis115), theposition175 is equivalent to the edge of thespherical lens105 for the signal beam165, but is equivalent to the center of thespherical lens110 for thesignal beam170. Similarly, theposition180 is away from the edge of thespherical lens105 for a distance ‘e’ while theposition180 is equivalent to the edge of thespherical lens110. As such, in order to make the signal beams165 and170 in phase, thecontrol mechanism160 configures thephase shifters150 and155 to modify (or adjust) the phase of the output signal transmitted by eitherRF element140 or145, or both output signals transmitted byRF elements140 and145. In this example, thecontrol mechanism160 can adjust the phase of the output signal transmitted byRF element145 by a value equivalent to the distance ‘e’ such that output signal beams165 and170 are in-phase.

In some embodiments, thecontrol mechanism160 is configured to automatically determine the phase modifications necessary to bring the output beams in-phase based on the positions of the RF elements. It is contemplated that a user can provide an input of a geographical areas to be covered by theantenna system100 and thecontrol mechanism160 would automatically move the positions of the RF elements to cover the geographical areas and configure the phase shifters to ensure that the output beams from the RF elements are in phase based on the new positions of the RF elements.

FIG. 1B illustrates an example of acontrol mechanism102 attached to theelement assembly103 that is associated with thespherical lens107. Themechanical module102 includes ahousing104, within which arod106 is disposed. Therod106 hasteeth108 configured to rotate agear112. The gear can in turn control the movement of theRF element109. Under this setup, a person can manually adjust the position of theRF element109 by moving therod106 up and down. It has been contemplated that therod106 can be extended to reach other element assemblies (for example, an element assembly and spherical lens that are stacked on top of the spherical lens107). That way, the rod can effectively control the movement of RF elements associated with more than one spherical lens.

In some embodiments, a phase shifter can be implemented within thesame mechanism102, by making at least a portion of therod106 using dielectric materials. When the rod includes dielectric materials, adjust the position of therod106 in this manner effectively modifies the phase of an output signal transmitted by theRF element109. It is noted that one can configure the position of therod106 and thegear112 such that the position of theRF element109 and the phase modification is in-sync. This way, one can simply provide a single input (moving the rod up or down by a distance) to adjust both the position of theRF element109 and the phase of the output signal.

It is also contemplated that an electric device (not shown) can be connected to the end of the rod (not attached to the gear112). The electric device can control the movement of therod106 based on an input electronic signal, thereby controlling the movement of theRF element109 and the phase adjustment of the output signal. A computing device (not shown) can communicatively couple with the electric device to remotely control theRF element109 and the phase of the output signal.

FIGS. 2A and 2B illustrate thespherical lens105 and theelement assembly120 from different perspectives. Specifically,FIG. 2A illustrates thespherical lens105 from a front perspective, in which the element assembly120 (including thetrack130 and the RF element140) appear to be behind thespherical lens105. In this figure, the signals emitting from theRF element140 are directed outward from the page.FIG. 2B illustrates thespherical lens105 from a back perspective, in which the element assembly120 (including thetrack130 and the RF element140) appear to be behind thespherical lens105. In this figure, the signals emitting from theRF element140 are directed into the page.

FIG. 3 illustrates anantenna300 of some embodiments in which the tracks associated with the spherical lens is two dimensional and each track associated with a spherical lens includes two RF elements. Theantenna300 is similar to theantenna100 ofFIG. 1. As shown, theantenna300 has twospherical lenses305 and310 aligned along avirtual axis315 in a three-dimensional space. Thespherical lens305 has an associatedelement assembly320, and thespherical lens310 has an associatedelement assembly325. Theelement assembly320 has atrack330, and similarly, theelement assembly325 has atrack335. Thetracks330 and335 are two dimensional.

In addition, each of thetracks325 and335 includes two RF elements. As shown, thetrack325 hasRF elements340 and345, and thetrack335 hasRF elements350 and355. The twodimensional tracks330 and335 allows the RF elements340-355 to move in a two dimensional field in their respective tracks. In some embodiments, theantenna300 creates groups of RF elements, where each group consists of one RF element from each element assembly. In this example, theantenna300 has two groups of RF elements. The first group of RF elements includes theRF element340 of theelement assembly320 and theRF element350 of theelement assembly325. The second group of RF elements includes theRF element345 of theelement assembly320 and theRF element355 of theelement assembly325. Theantenna300 provides a control mechanism and phase shifter for each group of RF elements. In this example, theantenna300 provides a control mechanism and phase shifter360 (all in one assembly) for the first group of RF elements and a control mechanism andphase shifter365 for the second group of RF elements. The control mechanism and phase shifters are configured to modify the positions of the RF elements within the group and to modify the phase of the output signals transmitted by the RF elements in the group such that the output signals coming out for the respectivespherical lens305 and310 are in-phase.

FIGS. 4A and 4B illustrates thespherical lens305 Figures and itselement assembly320 from different perspectives. Specifically,FIG. 4A illustrates thespherical lens305 from a front perspective, in which the element assembly320 (including thetrack330 and theRF elements340 and345) appear to be behind thespherical lens305. In this figure, the signals emitting from theRF element340 and345 are directed outward from the page. As shown, theRF elements340 and345 can move up and down (parallel to the virtual axis315) or sideways (perpendicular to the virtual axis315), as shown by the arrows near theRF element340.

FIG. 4B illustrates thespherical lens305 from a back perspective, in which the element assembly320 (including thetrack330 and theRF elements340 and345) appear to be behind thespherical lens305. In this figure, the signals emitting from theRF elements340 and345 are directed into the page. It is contemplated that more than two RF elements can be installed in the same element assembly, and different patterns (e.g., 3×3, 4×3, 4×4, etc.) of RF element arrangements can be formed on the element assembly.

Referring back toFIG. 3, it is noted that the RF elements that are in substantially identical positions with respect to their respective spherical lens are grouped together. For example, theRF element340 is paired with theRF element350 because their positions relative to their respective associatedspherical lenses305 and310 are substantially similar. Similarly, theRF element345 is paired with theRF element355 because their positions relative to their respective associatedspherical lenses305 and310 are substantially similar. It is contemplated that the manner in which RF elements are paired can affect the vertical footprint of the resultant beam (also known as polarized coincident radiation pattern) generated by the RF elements. As defined herein, the vertical footprint of an RF element means the coverage area of the RF element on a dimension that is parallel to the axis along which the spherical lenses are aligned. For practical purposes, the goal is to maximize the overlapping areas (also known as the cross polarized coincident radiation patterns) of the different resultant beams generated by multiple RF elements.

As such, in another aspect of the inventive subject matter, an antenna having an array of spherical lenses pairs opposite RF elements that are associated with different spherical lenses to cover substantially overlapping geographical areas. In some embodiments, each spherical lens in the array of spherical lenses has a virtual axis that is parallel with other virtual axes associated with the other spherical lenses in the array. One of the paired RF elements is placed on one side of the virtual axis associated with a first spherical lens and the other one of the paired RF elements is placed on the opposite side of the virtual axis associated with a second spherical lens. In some embodiments, the antenna also includes a control mechanism programmed to configure the paired RF elements to provide output signals to and/or receive input signals from substantially overlapping geographical areas.

FIG. 5 illustrates an example of such anantenna500 of some embodiments. Theantenna500 includes an array of spherical lens (includingspherical lenses505 and510) that is aligned along anaxis515. Although theantenna500 in this example is shown to include only two spherical lenses in the array of spherical lenses, it has been contemplated that theantenna500 can include more spherical lenses that are aligned along theaxis515 as desired.

Each spherical lens also includes an RF element arrangement axis that is parallel to one another. In this example, thespherical lens505 has an RFelement arrangement axis540 and thespherical lens510 has an RFelement arrangement axis545. Preferably, the RF element arrangement axes540 and545 are perpendicular to thevirtual axis515 along which thespherical lenses505 and510 are aligned, as shown in this example. However, it has been contemplated that the RF element arrangement axes can be in any orientation, as long as they are parallel with each other.

As shown, each spherical lens in the array has associated RF elements. In this example, thespherical lens505 has two associatedRF elements520 and525, and thespherical lens510 has two associatedRF elements530 and535. The RF elements associated with each spherical lens are placed along the surface of the spherical lens, on different sides of the RF element arrangement axis. As shown, theRF element520 is placed on top of (on one side of) the RFelement arrangement axis540 and theRF element525 is placed on the bottom of (on the other side of) the RFelement arrangement axis540. Similarly, theRF element530 is placed on top of (on one side of) the RFelement arrangement axis545 and theRF element525 is placed on the bottom of (on the other side of) the RFelement arrangement axis545.

Theantenna500 also includescontrol mechanisms550 and555 for coordinating groups of RF elements. As mentioned before, it has been contemplated that pairing opposite RF elements that are associated with different spherical lens (i.e., pairing RF elements that are on opposite sides of the RF element arrangement axis) provides the optimal overlapping vertical footprints. Thus, thecontrol mechanism550 is communicatively coupled with the RF element520 (which is placed on top of the RF element arrangement axis540) and the RF element535 (which is placed on the bottom of the RF element arrangement axis545) to coordinate theRF elements520 and535 to provide signal coverage of substantially the same geographical area. Similarly, thecontrol mechanism555 is communicatively coupled with the RF element525 (which is placed on the bottom of the RF element arrangement axis540) and the RF element530 (which is placed on top of the RF element arrangement axis545) to coordinate theRF elements525 and530 to provide signal coverage of substantially the same geographical area. In some embodiments, thecontrol mechanisms550 and555 also include phase shifters configured to modify the phase of the signals being outputted by their associated RF elements.

In addition to the requirement that the grouped RF elements have to be on different sides of the RF element arrangement axis, it is preferable that the distance between the RF elements and the RF element arrangement axis are substantially the same (less than 10%, and more preferably less than 5% deviation). Thus, in this example, the distance between theRF element520 and theaxis540 is substantially the same as the distance between theRF element535 and theaxis545. Similarly, the distance between theRF element525 and theaxis540 is substantially the same as the distance between theRF element530 and theaxis545.

While the RF elements520-535 are shown to be placed at fixed locations in this figure, in some other embodiments, theantenna500 can also includes tracks that enable the RF elements to move to different positions along the surface of their respective spherical lenses. In these embodiments, thecontrol mechanisms550 and555 are configured to coordinate their associated RF elements and phase shifters to send out synchronized signals to a covered geographical area.

In the example illustrated inFIG. 5, the RF element arrangement axes are arranged to be perpendicular to the axis along which the spherical lenses are aligned. As mentioned above, the RF element arrangement axes can be oriented in different ways.FIG. 6 illustrates anantenna600 having RF elements placed on different sides of RF element arrangement axes that are not perpendicular to the virtual axis along which the spherical lenses are aligned. Theantenna600 is almost identical to theantenna500. Theantenna600 has an array of spherical lens (includingspherical lenses605 and610) that is aligned along anaxis615. Although theantenna600 in this example is shown to include only two spherical lenses in the array of spherical lenses, it has been contemplated that theantenna600 can include more spherical lenses that are aligned along theaxis615 as desired.

Each spherical lens also includes an RF element arrangement axis that is parallel to one another. In this example, thespherical lens605 has an RFelement arrangement axis640 and thespherical lens610 has an RFelement arrangement axis645. As shown, the RF element arrangement axes640 and645 are not perpendicular to thevirtual axis615. By having the RF element arrangement axes in different orientations, theantenna600 can be adjusted to cover different geographical areas (closer to the antenna, farther away from the antenna, etc.).

As shown, each spherical lens in the array has associated RF elements. In this example, thespherical lens605 has two associatedRF elements620 and625, and thespherical lens610 has two associatedRF elements630 and635. The RF elements associated with each spherical lens are placed along the surface of the spherical lens, on different sides of the RF element arrangement axis. As shown, theRF element620 is placed on top of (on one side of) the RFelement arrangement axis640 and theRF element625 is placed on the bottom of (on the other side of) the RFelement arrangement axis640. Similarly, theRF element630 is placed on top of (on one side of) the RFelement arrangement axis645 and theRF element625 is placed on the bottom of (on the other side of) the RFelement arrangement axis645.

Theantenna600 also includescontrol mechanisms650 and655 for coordinating groups of RF elements. Thecontrol mechanisms650 and655 are configured to pair opposite RF elements that are associated with different spherical lens (i.e., pairing RF elements that are on opposite sides of the RF element arrangement axis). Thus, thecontrol mechanism650 is communicatively coupled with the RF element620 (which is placed on top of the RF element arrangement axis640) and the RF element635 (which is placed on the bottom of the RF element arrangement axis645) to coordinate theRF elements620 and635 to provide signal coverage of substantially the same geographical area. Similarly, thecontrol mechanism655 is communicatively coupled with the RF element625 (which is placed on the bottom of the RF element arrangement axis640) and the RF element630 (which is placed on top of the RF element arrangement axis645) to coordinate theRF elements625 and630 to provide signal coverage of substantially the same geographical area. In some embodiments, thecontrol mechanisms650 and655 also include phase shifters configured to modify the phase of the signals being outputted by their associated RF elements.

State of art antennas currently used for wireless broadband networks provide two cross polarized coincident radiation patterns commonly referred to as ports of the antenna. There is a growing demand from the wireless operator community for four coincident radiation patterns with good de-correlation of radio signals present on each port. Current approach for four coincident radiation patterns is to deploy redundant cross polarized antenna solutions. The method described above for pairing opposite RF elements provides a novel approach in achieving four predominantly coincident radiation patterns (two for each RF element).

It should be apparent to those skilled in the art that many more modifications besides those already described are possible without departing from the inventive concepts herein. The inventive subject matter, therefore, is not to be restricted except in the spirit of the appended claims. Moreover, in interpreting both the specification and the claims, all terms should be interpreted in the broadest possible manner consistent with the context. In particular, the terms “comprises” and “comprising” should be interpreted as referring to elements, components, or steps in a non-exclusive manner, indicating that the referenced elements, components, or steps may be present, or utilized, or combined with other elements, components, or steps that are not expressly referenced. Where the specification claims refers to at least one of something selected from the group consisting of A, B, C . . . and N, the text should be interpreted as requiring only one element from the group, not A plus N, or B plus N, etc.

Claims (19)

What is claimed is:

1. An antenna comprising:

a plurality of lenses, comprising a first and a second spherical lens;

a first assembly disposed along a first exterior surface of the first spherical lens, the first assembly comprising a first RF element configured to provide a first output signal;

a second assembly disposed along a second exterior surface of the second spherical lens, the second assembly comprising a second RF element configured to provide a second output signal;

a first phase shifter connected to the first and second RF elements;

and a control mechanism comprising an electronic device to:

(a) receive a geographical area to be covered by the antenna, and

(b) transmit an electronic signal to the first phase shifter to shift at least one of a first phase of the first output signal and a second phase of the second output signal as a function of a relative position of the first RF element and a relative position of the second RF element, respectively, such that the first output signal and the second output signal are in-phase for the geographical area.

2. The antenna ofclaim 1, wherein the first phase shifter is configured to coordinate the first RF element with the second RF element to modify the first phase of the first output signal and the second phase of the second output signal so that the first and second output signals are in-phase after passing through the first and second spherical lenses, respectively.

3. The antenna ofclaim 1, wherein the first phase shifter modifies the first phase of the first output signal by time-shifting a phase of the first output signal.

4. The antenna ofclaim 3, wherein the control mechanism is further configured to move the first and second RF elements such that the first and second output beams cover the geographic area.

5. The antenna ofclaim 1, wherein the first and second spherical lenses are both aligned along a virtual axis.

6. The antenna ofclaim 1, further comprising:

a second phase shifter,

wherein the first assembly further comprises a third RF element configured to provide a third output signal, and

wherein the second assembly further comprises a fourth RF element configured to provide a fourth output signal, and

wherein the electronic device further:

(a) receives an alternative geographical area to be covered by the antenna, and

(b) transmits a second electronic signal to the second phase shifter to shift at least one of a third phase of the third output signal and a fourth phase of the fourth output signal as a function of a relative position of the third RF element and a relative position of the fourth RF element, respectively, such that the third output signal and the fourth output signal are in-phase for the alternative geographical area.

7. The antenna ofclaim 1, wherein the first assembly further comprises a third RF element that provides a third output signal.

8. The antenna ofclaim 7, wherein the second assembly further comprises a fourth RF element that provides a fourth output signal.

9. The antenna ofclaim 8, wherein the first phase shifter automatically shifts a third phase of the third output signal and a fourth phase of the fourth output signal according to relative position of the third RF element and a relative position of the fourth RF element, respectively.

10. The antenna ofclaim 1, wherein the first and second spherical lenses are substantially identical.

11. The antenna ofclaim 1, wherein the first phase shifter comprises an electronic circuit.

12. The antenna ofclaim 1, wherein each of the spherical lenses has a surface area that substantially conforms between 50% to at least 90% to a shape of a sphere.

13. The antenna ofclaim 12, wherein the first phase shifter is configured to coordinate the first RF element with the second RF element to modify the first phase of the first output signal and the second phase of the second output signal so that the first and second output signals are in-phase after passing through the first and second spherical lenses, respectively.

14. The antenna ofclaim 1, wherein each of the plurality of lenses comprises at least one of a single layer of dielectric material and multiple layers of dielectric material.

15. The antenna ofclaim 1, wherein at least one of the first and second RF elements is fixed in place.

16. The antenna ofclaim 1, further comprising a plurality of RF elements focused by at least some of the plurality of lenses on a same geographic area to provide increased capacity within the same geographic area.

17. The antenna ofclaim 1, further comprising paired RF elements that transmit output signals and receive input signals from substantially overlapping geographical areas.

18. The antenna ofclaim 1, wherein the first phase shifter is configured to modify the first phase of the first output signal to a first desired phase and to modify the second phase of the second output signal to a second desired phase so that the first and second output signals are in-phase after passing through the first and second spherical lenses, respectively.

19. A method of adjusting an antenna's coverage area, wherein the antenna has a first radio frequency (RF) element associated with a first spherical lens, a second RF element associated with a second spherical lens, and a phase shifter communicatively coupled with the first and second RF elements, the method comprising the steps of:

receiving a geographical area to be covered by the antenna;

determining a relative position between a first position of the first RF element along a surface of the first spherical lens and a second position of the second RF element along a surface of the second spherical lens, wherein the first RF element transmits a first output signal and wherein the second RF element transmits a second output signal; and

transmitting an electronic signal from an electronic device of a control mechanism to a phase shifter to automatically shift at least one of a first phase of the first output signal and a second phase of the second output signal as a function of a relative position determined and beam direction of the first RF element and a relative position of the second RF element, respectively, such that the first output signal and the second output signal are in-phase for the geographical area.

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